Add npm updates and node 10 build

[manoharuss]

• [x] turned on travis builds and added node 6,8,10 lts versions into travis
• [x] removed node 0.10, 4.x because they have met EOL
• [x] deleted appveyor project and removed appveyor project files
• [x] updated changelog for minor release

[manoharuss]

Going to merge and make a new release

[manoharuss]

✅ Turned off travis builds after new release https://www.npmjs.com/package/@mapbox/abaculus